填空题 Malaria is a very serious disease that kills more children under the age of five than any other disease. People get malaria when they are bitten by{{U}} (1) {{/U}}called mosquitoes. The mosquitoes{{U}} (2) {{/U}}which enter a person's blood and cause malaria. Carter Dibbs is an American doctor who works on the{{U}} (3) {{/U}}for the United States Agency for International Development. Doctor Dibbs says the parasite that causes malaria is much{{U}} (4) {{/U}}, such as the virus that causes polio. He says the malaria parasite{{U}} (5) {{/U}}so that it is more difficult to make a vaccine that is safe and will{{U}} (6) {{/U}}. Malaria vaccines are now{{U}} (7) {{/U}}in Burkina Faso and Mall. Vaccines are being tested on children in Mozambique and Mall. Many organizations are{{U}} (8) {{/U}}. They include U, S. A. I. D, the American military, American health organizations, {{U}}(9) {{/U}}. To make sure that a vaccine will{{U}} (10) {{/U}}, it must be tested on many people in many different places. Doctor Dibbs says the people who join the vaccine tests are as important to{{U}} (11) {{/U}}as the scientists. People are told about the tests during public meetings{{U}} (12) {{/U}}. Doctor Dibbs says people should{{U}} (13) {{/U}}that could happen to their bodies if they take the medicine that is being tested. Adults or parents of children must agree to the vaccine test. Adults receive{{U}} (14) {{/U}}the vaccine medicine. The children receive either the malaria vaccine or a different medicine that{{U}} (15) {{/U}}a different disease. Then health care workers{{U}} (16) {{/U}}to see if they show any signs of malaria. The results of the tests must be compared to people who have not{{U}} (17) {{/U}}. The vaccine is successful if{{U}} (18) {{/U}}who receive it do not show any signs of malaria for one year. Then the United States government will be asked to{{U}} (19) {{/U}}. However, it could still take another five years before{{U}} (20) {{/U}}to give to all the children in Africa and around the world.